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Could you try to make it > more concise? I agree. It looks like AI generated. > >> Signed-off-by: Zhiteng Qiu >> --- >> @@ -1344,7 +1344,19 @@ static int migrate_folio_unmap(new_folio_t get_ne= w_folio, >> /* Establish migration ptes */ >> VM_BUG_ON_FOLIO(folio_test_anon(src) && >> !folio_test_ksm(src) && !anon_vma, src); >> - try_to_migrate(src, mode =3D=3D MIGRATE_ASYNC ? TTU_BATCH_FLUSH : 0); >> + enum ttu_flags ttu =3D mode =3D=3D MIGRATE_ASYNC ? TTU_BATCH_FLUSH : = 0; >> + >> + /* >> + * Batching only pays off when the rmap walk can meet more than >> + * one PTE. A lone order-0 folio with a single mapping has >> + * exactly one: batching it gains nothing, and it leaves >> + * mm->tlb_flush_batched pending, so later page table changes >> + * in this mm (e.g. NUMA scanning) flush the whole mm. This comment can be simplified. >> + */ >> + if (single_folio && !folio_test_large(src) && >> + !folio_maybe_mapped_shared(src)) >> + ttu &=3D ~TTU_BATCH_FLUSH; > > Is it possible to use a simplified version as below? > > enum ttu_flags ttu =3D 0; > > if (mode =3D=3D MIGRATE_ASYNC && > (!single_folio || folio_mapcount(src) > 1)) LGTM, but I would keep folio_maybe_mapped_shared() to clarify the intent. Would (!single_folio || folio_maybe_mapped_shared(src)) work? > ttu =3D TTU_BATCH_FLUSH; > --=20 Best Regards, Yan, Zi